Rotary food dehydrating apparatus with tiltable tray means



Dec. 26, 1967 M. s. GOLDMAN 3,359,644

ROTARY FOOD DEHYDRATING APPARATUS WITH TILTABLE TRAY MEANS OriginalFiled July 28, 1966 FIG. 5

INVENTOR. MILTON S. GOLDMAN ATTORN- United States Patent 3,359,644ROTARY FOOD DEHYDRATING APPARATUS WETH TILTABLE TRAY MEANS Milton S.Goldman, 1101 Graydon Ave., Norfolk, Va. 23507 Continuation ofapplication Ser. No. 568,427, July 28, 1966. This application Feb. 10,1967, Ser. No. 615,246 Claims. (Cl. 3458) ABSTRACT OF THE DISCLOSURE Adehydration apparatus including a readily accessible insulated chamber,a vertically rotatable open-framed rack device mounted within thechamber for carrying a plurality of vertically spaced, parallellydisposed trays at various preselected angles of inclination, an airheater mounted within the chamber, a fan for moving heated air from thevicinity of the heater through the rack device, and means forestablishing a flow of air through the chamber.

This application is a continuation of my copending application, Ser. No.568,427, filed July 28, 1966, now abandoned.

This invention relates generally to apparatus for the dehydration ofmaterials, and more particularly to apparatus available for householdand small institutional use in dehydrating foods for the preservationthereof in a superior condition.

The preservation of foods for prolonged periods first became a realitywith the development and introduction of canning processes. The freezingof foods has more recently become popular on a broad basis due to thefact that the freezing process less seriously affects the taste andnutritional value of a wide variety of foods than does the canningprocess. It is now considered that the preservation of foods bydehydration is far better than the preservation thereof by canning orfreezing methods. Fruits, vegetables, poultry, meats, and many otherfood items, when dehydrated, may be stored safely for years at normalroom temperatures without fear of spoilage, as bacteria will not live inthe minimal moisture content of dehydrated foods. As the sole purposeor" the dehydration process is the removal of the moisture content offoods, the original nutrients and flavor elements remain, and afteryears of storage are still present when the dehydrated foods arereconstituted by the simple addition of water. Inasmuch as the moisturecontent of most foods ranges from 70% to 90%, it will further be obviousthat far less storage space is required for foods that have beendehydrated than for the same foods in their original condition.

Those active in the field to which the present invention pertains haveprovided apparatus for the dehydration of foods such as that shown, forexample, in US. Patent No. 3,016,627 granted on Jan. 16, 1962 to B. G.Freund, and which has since been assigned to the present applicant. Theapparatus disclosed in US. Patent No. 3,016,- 627 is not, however,considered to be well suited for use in the household or in smallinstitutions, being large and cumbersome, as well as overly complex, Theapparatus for dehydrating foods herein disclosed, however, is deemed toadequately fill a need not satisfied by the prior art and to overcomethe drawbacks of such prior art devices as those shown in US. Patent No.3,016,627.

Accordingly, an object of the present invention is the provision ofsimplified apparatus for the dehydration of materials.

Another object of the instant invention is the provision of compact andsimplified apparatus for the preservatory dehydration of foodsparticularly adapted for household and small institutional use.

According to the present invention, the foregoing and other objects areattained by providing apparatus including a readily accessible insulatedchamber. a substantially vertically disposed open-framed rack devicesituated within the insulated chamber upon which trays adapted tocontain foods to be dehydrated may be parallelly racked at variouspreselected angles of inclination, and means for rotating the rackdevice substantially about the vertical axis thereof. The apparatusfurther includes an electric heating unit situated Within the insulate-dchamber, a fan for directing the heat thereby produced through theopen-framed rack device and the trays positioned thereon, an inlet foradmitting filtered fresh air into the insulated chamber, and a conduithaving an exhaust fan mounted therein for removing warm and moistureladen air from the insulated chamber.

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily apparent as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawing wherein:

FIG. 1 is a front elevational view of the dehydration apparatus;

FIG. 2 is a sectional, side elevational view of the dehydrationapparatus, taken along the line 22 of FIG. 1;

FIG. 3 is a plan view of the open-framed rack device;

FIG. 4 is a sectional, elevational view of the openframed rack device,taken along the line 44 of FIG. 3; and

FIG. 5 is a side elevational view of the open-framed rack device, takenalong the line 55 of FIG. 3.

Referring now more particularly to the drawing, wherein like referencenumerals designate the same or identical parts throughout the severalviews, and more specifically to FIGS. 1 and 2, there is shown apparatus,generally designated by the reference numeral 11, for dehydrating foodsand the like. Apparatus 11 includes a cabinet 12 incorporating aninsulated chamber 13 having top and bottom Walls 14, a rear wall 15, andside walls 16. A door 17 hinged at 18 along one vertical edge thereof toa side wall 16 of insulated chamber 13, and having a conventional handle19 adjacent the other vertical edge thereof, is provided for closinginsulated chamber 13. A suitably glazed viewport 21 is provided in door17 to permit observation of the interior of insulated chamber 13 whenthe door 17 is closed. Each of the top and bottom walls 14, rear Wall15, and side walls 16 of insulated chamber 13, as well as the door 17,are preferably formed of a single panel member of the type havingparallelly spaced surface sheets of thin metal with a suitableinsulating material disposed there-between, and having suitable metallicedge elements extending between the panel surface sheets along the edgesthereof, where required. The panel members defining the top and bottomwalls 14, rear wall 15, and side walls 16 are suitably joined togetherto form the insulated chamber 13. The cabinet 12 incorporating theinsulated chamber 13 also effectively encloses a volume of space lyingat least above, behind, and beneath the insulated chamber 13; the spaceso enclosed being bounded by a cabinet upper element 22, a cabinet lowerelement 23, and a cabinet rear wall 24, as well as cabinet side walls25, which may also extend over the side walls 16 of insulated chamber13, if desired. It will be noted that the cabinet lower element 23,rather than extending completely around the volume of space underlyinginsulated chamber 13, is open at the bottom thereof for the purpose ofaccess.

It is to be particularly understood that the specific structural detailsof the cabinet incorporating the insulated chamber set forthhereinbefore are merely exemplary, and that any other suitableconstruction of a cabinet incorporating such an insulated chamber may beemployed in the actual practice of the present invention withoutdeparting from the spirit thereof.

During operation of apparatus 11, a constant flow of air into and thenout of the insulated chamber 13 is required. Accordingly, the apparatus11 further includes an air inlet port extending between the exteriorthereof and insulated chamber 13 in which a suitable air filter element26 is mounted, as illustrated in FIG. 2. Further, apparatus ll alsoincludes an air exhaust conduit 27 extending from an opening formedthrough the rear wall of insulated chamber 13 and out of cabinet 12through the rear wall 24 thereof equipped with a suitable electricexhaust fan 28 mounted therein. The operation of exhaust fan 28 draws asteady stream of air through the filter 26 into the insulated chamber13, where it picks up moisture removed from food :by the operation ofthe apparatus 11, and then discharges the moisture laden air from theinsulated chamber 13.

The apparatus 11 also includes a radiant heater 29 of the electricalresistance type mounted in insulated chamber 13 on the rear wall 15thereof. Heater 29 preferably includes a length of sinuously' shapedheavy heating wire, disposed a small distance from the rear wall 15 ofinsulated chamber 13 and parallelly therewith over a considerable extentthereof.

An-electric motor 31 is mounted on the exterior surface of rear wall 15of insulated chamber 13; the shaft element thereof extending through asuitable opening formed through rear wall 15 of insulated chamber 13.The shaft element of motor 31 passes between the folds of the heatingwire of heater 29 and into insulated chamber 13, and a fan blade 32 ismounted on the shaft element of motor 31 near the extremity thereofwithin insulated chamber 13. Rotation of the fan blade 32 duringoperation of motor 31 draws heat from the vicinity of the heater 29disposed between the fan :blade 32 and the rear wall 15 of insulatedchamber 13, setting up a current of heated air for the purpose morefully set forth hereinafter.

An electric motor 33 is mounted beneath the insulated chamber 13 on thecabinet lower element 23; the shaft element 34 of motor 33 projectingvertically upwardly through the cabinet lower element 23 and the bottomwall 14 of insulated chamber 13. An open-framed rack device, generallydesignated by the reference numeral 35 and shown in frontal elevation inFIG. 2, is mounted upon the upper end of shaft element 34 of motor 33;rack device 35 being rotatable substantially about its own vertical axisduring operation of the motor 33.

Referring now more specifically to FIGS. 3-5, as well as to FIG. 2, .itwill be seen that rack device 35 includes a horizontally disposed lowerframe section, generally designated by the reference numeral 36. Framesection 36 includes elongated, horizontally disposed, metallic front andrear bars 37 and a pair of elongated, horizontally disposed, metallicside bars 38 all interconnected to define the periphery of a rectangle;the bars 37 and 38 all being identically rectangular in section withtheir longer, sectional axes vertically disposed. Frame section 36further includes a pair of elongated, horizontally disposed, metallicangle elements 39 extending between the bars 37 and symmetricallysituated with respect to the midpoints of thebars 37; the angle elements39 each having a horizontally disposed flange with a lower surfacesituated in the plane of the lower edges of the bars 37 and 38. Ametallic cylindrical element 41 having a horizontally disposed uppersurface is connected to the lower surface of the horizontally disposedflange of each ,of

the angle elements 39; the centroid of the cylindrical element 41 beingdisposed directly beneath the centroid of frame section 36. Thecylindrical element 41 is in turn axially mounted upon the shaft element34 of motor 33; the operation of motor 33 thereby causing the lowerframe section 36 of rack device 35 to rotate about its own verticalcentroidal axis.

Rack device 35 further includes a horizontally disposed upper framesection, generally designated by the reference numeral 42. Frame section42 includes horizontally disposed front and rear bars 37 identical tothe front and rear :bars 37 of frame section 36, and a pair ofhorizontally disposed side bars 38 identical to the side bars 38 offrame section 36. The bars 37 and 38 of upper frame section 42 areinterconnected identically to the interconnection of the bars 37 and 38of lower frame section 36.

The upper frame section 42 of rack device 35 is congruently supported adistance above the lower frame section 36 thereof by a pair of metallicfront standards 43 and a pair of metallic rear standards 44. The frontstandards 43 are angle members; each standard 43 having the outersurface of one flange thereof connected to the front end of the outersurface of a side bar 38 of the frame sections 36 and 42 and having theother flange thereof extending away from the frame sections 36 and 42.The rear standards 44 are also angle members; each standard 44 havingthe inner surface of one flange thereof connected to the rear end of theouter surface of a side bar 38 of the frame sections 36 and 42 andhaving the inner surface of the other flange thereof connected to a sideend of the outer surface of the rear bar 37 of the frame sections 36 and42.

A plurality of horizontally disposed, vertically spaced, metallic anglemembers 45 substantially equal in length to side bars 38 are connectedbetween one of the front standards 43 and one of the rear standards 44of the rack device 35. One of the flanges of each of the angle members45 is vertically disposed and, being situated between a side bar 38 ofeach of the frame sections 36 and 42, is connected to the front standard43 and the rear standard 44 similarly to the connection of these sidebars 38 thereto. The other flange of each of the angle members 45extends horizontally from the low edge of the Vertical flange thereofinto the rack device 35.

A horizontally disposed, metallic support bar 46 substantially equal inlength to side bars 38 is connected between the front standard 43 andthe rear standard 44 of the rack device 35 not carrying the anglemembers 45. The support bar 46 is substantially identical in section tothe side bars 38, and is situated directly beneath a side bar 38 ofupper frame section 42; the connection of the support bar 46 to thestandard 43 and the standard 44 being the same as the connections of theside bars 38 thereto.

A pair of identical, metallic, vertically disposed sliding members 47rectangular in section are positioned with the inner surfaces thereofbearing against the outer surfaces of the support bar 46 and the sidebars 38 disposed thereabove and therebelow, with their long sectionalaxes parallel to the support bar 46 and side bars 38. An elongatedlongitudinal slot 48 is formed through each sliding member 47 near eachof the ends thereof. The outer surfaces of the support bar 46 and theside bar 38 disposed therebeneath each carry a pair of studs 49; thecorresponding studs on support bar 46 and the side bar 38 beingvertically aligned. A stud 49 extends through each slot 48 of eachsliding member 47; the outer extremity of each stud 49 carrying a knob51, or the like, greater in diameter than the width of the slots 48 formaintaining the relationship of the parts involved. The studs 49 are sopositioned on the support bar 46 and the side bar 38 that one verticalmember 47 is vertically disposed closely adjacent a front standard 43and the other vertical member 47 is vertically disposed closely adjacenta rear standard 44.

A plurality of horizontally disposed, vertically spaced, metallic anglemembers 52 substantially identical to the angle members 45 are connectedbetween the inner surfaces of the sliding members 47; the slidingmembers 47 when so interconnected being similarly vertically positioned.One of the flanges of each of the angle members 52 is verticallydisposed and, being situated between the support bar 46 and the side bar38 disposed therebelow, makes sliding contact with the standards 43 and44 adjacent thereto. The other flange of each of the angle members 52extends from the low edge of the vertical flange thereof horizontallyinto the rack device 35.

The pair of sliding members 47 and the angle members 52 connectedtherebetween move upwardly and downwardly as a unit a distancesubstantially equal to the length of the slots 48. When the lowermostangle member 52 is at the lower limit of its range of travel it issubstantially at the vertical level of the lowermost angle member 45.The remaining angle members 52 and 45 correspond in number, and thevertical spacing of the angle members 52 and the angle members 45 ispreferably identical.

' The force of gravity will normally maintain the sliding members 47 andthe angle members 52 connected therebetween at the lowermost limit ofthe range of travel thereof. In order to maintain the angle members 52at various more elevated preselected positions, an elongated bar 53 ispivotally connected near one end thereof to the outermost surface of theside bar 38 disposed below the lowerermost angle member 52; the bar 53carrying near the other end thereof a shaft 54 extending inwardlytherefrom between the lowermost angle member 52. and the side bar 38disposed therebeneath. The shaft 54 also extends outwardly in theopposite direction from the bar 53 for use as a manually graspablehandle. Further, a plurality of bores 55 are formed through the bar 53intermediate its point of pivotal connection to the side bar 38 and theshaft 54 extending therethrough. When the shaft 54 is lifted to elevatethe sliding members 47 and the angle members 52, a bolt 56 is passedthrough one of the bores 55 and, bearing against the upper surface ofthe side bar 38 to which the bar 53 is connected, serves to maintain thesliding members 47 and the angle members 52 at a preselected elevatedposition. A nut 57 may be placed on the bolt 56 to prevent theinadvertent withdrawal thereof from the bore 55.

An elongated element 58 is hingedly connected to the front surface ofone of the front standards 43 of rack device 35,- and is swingablebetween a position obstructing frontal access to'the interior of therack device 35 and a position in which it in no way interferes withfrontal access to the interior of rack device 35. The front bar 37 ofthe upper frame section 42 of rack device 35 carries a conventional,manually operated sliding bolt 59 moveable to secure the elongatedelement 58 in the position obstructing frontal access to the interior ofrack device 35. -A frontal section of the cabinet upper element 22 ofcabinet 12 may include a control panel 61 carrying switches foractivating the exhaust fan 28, the electric motor 31, the electric motor33, the radiant heater 29, and the electric light bulbs which may beplaced in the insulated chamber 13 to illuminate the interior thereof,as well as thermostatic control means to regulate the amount of heatproduced by the heater 29. The wires leading from control panel 61 tothese various devices pass through the volume of space enclosed bycabinet 12 exteriorly of the insulated chamber 13, but a showing of thisconventional wiring is not included in the drawing as unnecessary.

Foods to be processed in the apparatus 11 are first minced, diced,sliced, or shredded to facilitate the removal of moisture therefrom, andthen blanched in the usual way. The foods thus prepared are then placedin trays 62 which are substantially equal in width to the distancebetween the vertical flanges of an angle member 45 and the angle member52 disposed substantially at the same level when in its lowermostposition. The trays 62,

which are substantially equal in length to the length of the anglemembers 45 and 52, are fairly shallow in depth and have highly porousbottoms which may be sheet metal having about fifty perforations to thesquare inch, each such perforation being about inch in diameter, orwhich may be correspondingly porous metallic screen material.

A plurality of charged trays 62 equal in number to the number of anglemembers 45 of the rack device 35 are substantially horizontally placedin the rack device 35; one side edge of each tray 62 resting on an anglemember 45 and the other side edge thereof resting on an angle member 52disposed in its lowermost position. The angle members 52 are then raisedto their uppermost positions, tilting the trays 62 to a maximum angle ofinclination, and the bolt 56 is secured in the bore 55 nearest the pivotpoint of bar 53, as shown in FIG. 5, for initially maintaining thismaximum angle of inclination of the trays 62. When the trays 62 havebeen so positioned, the elongated element 58 is moved to the position inwhich it obstructs frontal access to the interior of the rack device 35,and latched in this position by the sliding bolt 59. The angle ofinclination of trays 62 is always kept as high as possible; the fooditems placed therein thereby receiving maximum exposure to the flow ofheated air. The door 17 is then closed, and the dehydration process iscommenced in apparatus 11 by switching on the exhaust fan 28 to draw airthrough insulated chamber 13, by turning on the heater 29, by activatingthe electric motor 31 for fan blade 32 to direct a flow of gently heatedair against the trays 62 disposed in rack device 35, and by starting theelectric motor 33 to cause rack device 35 to rotate substantially aboutits own vertical axis at a moderate rate. This rotational movement ofthe rack device 35 establishes centrifugal forces in the food itemsdisposed in the trays 62, bringing the moisture therein to the surfaceof the particles thereof. The gently heated air blown over the foodparticles picks up this ejected moisture, which is subsequentlydischarged from the insulated chamber 13 through the exhaust conduit 27.Care should be exercised in assuring that too much heat is not used inthe process, since case hardening of the food particles may be theresult thereof, producing food particles exteriorly tough and chalky,and not completely interiorly dried.

As the food placed in the trays 62 becomes drier during the dehydratingoperation, the particles thereof lose some of their tendency to sticktogether and begin to slip toward the low side of the trays 62. Whenthis occurs, which may be readily observable through the viewport 21 ofdoor 17, the process is halted to allow the angle of inclination of thetrays 62 to be reduced, which may be simply accomplished by moving thebolt 56 to another of the bores 55 formed through the bar 53. The foodparticles having been properly redistributed over the trays 62, thedehydration process is resumed. The reduction of the angle ofinclination of the trays 62 may be further reaccomplished in like mannerduring the succeeding stages of the operation. When the dehydrationprocess has been completed, the bolt 59 is moved to allow the elongatedelement 58 to be swung aside for removal of the trays 62 from apparatus11.

Obviously, many modifications andvariations of the present invention arepossible in the light of the foregoing teachings. It is therefore to beunderstood that within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. Apparatus .for the dehydration of materials, comprising:

(A) a chamber;

(B) means for producing a flow of air through said chamber;

(C) a heat source disposed within said chamber;

(D) means for directing a flow of heated air away from said heat source;

(E) a rack device situated within said chamber in the path of said flowof heated air, said rack device including (a) a lower frame section,

(b) a plurality of parallelly disposed standards connected to said lowerframe section and projecting upwardly therefrom,

(c) means connected to at least one of said standards for partiallysupporting a tray charged with materials to be dehydrated,

(d) means for further partially supporting a tray charged with materialsto be dehydrated interconnected with at least one of the other of saidstandards for limited vertical movement with respect thereto, said meansconnected to said one standard for partially supporting a tray and saidmeans for further partially supporting a tray interconnected with saidother standard for limited vertical movement with respect theretocooperating to completely support a tray,

(e) means for maintaining at a plurality of preselected points withinthe range of limited vertical movement thereof said means for partiallysupporting a tray interconnected with said other of said standards, aswell as (f) means movably connected to one of said standards forrestraining lateral movement of a tray placed on said rack device; and

(F) means for rotating said rack device about a vertical axis passingsubstantially centrally therethrough.

2. The apparatus according to claim 1, wherein said means connected toat least one of said standards include a first plurality of verticallyspaced horizontally disposed members each having a section adapted toprevent lateral movement of said tray in at least one direction.

3. The apparatus according to claim 2, wherein said means for furthersupporting said tray interconnected with said other of Said standardsfor limited vertical movement with respect thereto includes a secondplurality of vertically spaced, horizontally disposed members eachhaving a section adapted to support said tray and further having asection adapted to prevent lateral movement of said tray in at least oneother direction.

4. The apparatus according to claim 3, wherein said means formaintaining at a plurality of preselected points within the range oflimited vertical movement thereof said means for partially supporting atray interconnected with said other of said standards includes a barpivotally connected to said lower frame section having a shaft extendingfrom the end thereof remote from said pivotal connection engageable withone of said second plurality of vertically spaced, horizontally disposedmembers.

-. Apparatus for the dehydration of materials, comprising:

(A) an operationally closed insulated chamber;

'(B) means for establishing a flow of air through said chamber;

(C) a heat source disposed within said chamber;

(D) means for directing a flow of heated air away from said heat source;

(E) an open-framed rack device situated within said chamber in the pathof said flow of heated air directed away from said heat source, saidrack device including (a) a horizontally disposed, rectangular, lowerframe section,

(b) a front standard connected in the vicinity of the lower extremitythereof to said lower frame section adjacent each of two of the cornersthereof and projecting vertically upwardly therefrom, and a rearstandard connected in the vicinity of the lower extermity thereof tosaid lower frame section adjacent each of the two remaining cornersthereof and projecting vertically upwardly therefrom, each of said frontstandards having an inner surface abutting a separate single side ofsaid lower frame section, each of said rear standards having a firstinner surface abutting a separate single side of said lower framesection also abutted by said inner surface of one of said frontstandards, and each of said rear standards further having a second innersurface abutting the opposite ends of still another separate single sideof said lower frame section,

(c) a horizontally disposed, rectangular, u-pper frame sectionsubstantially identical to said lower frame section congruentlypositioned above said lower frame section and connected to saidstandards in the vicinity of the upper extremities thereof similarly tothe connection of said lower frame section thereto,

(d) a first plurality of horizontally disposed, vertically spacedmembers each adapted to support one edge of a tray connected between afirst of said front standards and a first of said rear standards, eachof said first plurality of members having at least a horizontallydisposed flange extending into the space between said lower framesection and said upper frame section and in juxtaposition with saidinner surface of said first front standard and with said first andsecond inner surfaces of said first rear standard,

(e) at least one vertically disposed member positioned between thesecond of said front standards and the second of said rear standards andconnected to said rack device for limited vertical movement with respectthereto,

(f) a second plurality of horizontally disposed,

vertically spaced members each adapted to support another edge of a trayextending between the second of said front standards and the second ofsaid rear standards, each of said second plurality of members beingconnected to said vertically disposed member positioned between saidsecond front standard and said second rear standard and having at leasta horizontally disposed flange extending into the space between saidlower frame section and said upper frame section and in verticallysliding juxtaposition with said inner surface of said second frontstandard and with said first and second inner surfaces of said secondrear standard,

(g) means for maintaining at a plurality of preselected points withinthe range of limited vertical movement thereof said vertically disposedmember positioned between said second front standard and said secondrear standard and said second plurality of members connected 'to saidvertically disposed member positioned between said second front standardand said second rear standard, as well as (h) means moveably connectedto one of said front standards for restraining frontal movement of eachof a plurality of trays positionable on said rack device; and

(F) means for rotating said rack device about a vertical axis passingsubstantially centrally therethrough.

6. The apparatus according to claim 5, wherein each of said firstplurality of horizontally disposed, vertically spaced members connectedbetween said first front standard and said first rear standard is anangle member further having a vertically disposed flange extendingupwardly from said horizontally disposed flange thereof and injuxtaposition with said inner surface of said first front standard andwith said first inner surface of said first rear standard, the thicknessof said vertical flange of each of said first plurality of angle membersbeing less than the width of said second inner surface of said firstrear standard; and wherein each of said second plurality of horizontallydisposed, vertically spaced members extending between said second frontstandard and said second rear standard is an angle member further havinga vertically disposed flange extending upwardly from said horizontallydisposed flange thereof and in vertically sliding juxtaposition withsaid inner surface of said second front standard and with said firstinner surface of said second rear standard, the thickness of saidvertical flange of each of said second plurality of angle members beingless than the width of said second inner surface of said second rearstandard; said first plurality of angle members and said secondplurality of angle members corresponding in number and in verticalspacing; the lowermost of said first plurality of angle members and saidsecond plurality of angle members being disposed at substantially thesame level when said vertically disposed member positioned between saidsecond front standard and said second rear standard is at the lowermostlimit of the range of vertical movement thereof and adapted to supportopposed edges of a rectangular tray positionable thereon in substantialabutment with said vertical flange of said lowermost of said firstplurality of angle members, said vertical flange of said lowermost ofsaid second plurality of angle members, said second inner surfaces ofsaid first and second rear standards, and said means moveably connectedto one of said front standards for restraining frontal movement of eachof a plurality of trays positionable on said rack device; each of theother of said first plurality of angle members being adapted tocooperate with the corresponding one of said second plurality of anglemembers to similarly support another like tray.

7. The apparatus according to claim 6, including a second verticallydisposed member positioned between said second front standard and saidsecond rear standard and connected to said rack device for limitedvertical movement with respect thereto as well as connected to each ofsaid second plurality of angle members, said one vertically disposedmember and said second vertically disposed member positioned betweensaid second front standard and said second rear standard beinghorizontally spaced and disposed at substantially the same level.

8. The apparatus according to claim 7, wherein said means formaintaining at a plurality of preselected points within the range oflimited vertical movement thereof said one vertically disposed memberand said second vertically disposed member positioned between saidsecond front standard and said second rear standard and said secondplurality of angle members includes a bar pivotally connected near oneend thereof to said lower frame section between said second frontstandard and said second rear standard having a shaft projectingtherefrom near the end thereof remote from said pivotal connection andunderlying the lowermost angle member of said second plurality of anglemembers between said one vertically disposed member and said secondvertically disposed member positioned between said second front standardand said second rear standard.

9. The apparatus according to claim 8, wherein said means moveablyconnected to one of said front standards for restraining frontalmovement of each of a plurality of trays positionable on said rackdevice includes a vertically disposed bar vertically hinged to said oneof said front standards and swingable between a position partiallyblocking frontal access to the interior of said rack device and aposition affording complete frontal access to the interior of said rackdevice, as well as a manually moveable bolt carried by said upper framesection for latching said vertically hinged bar into said positionpartially blocking frontal access to the interior of said rack device.

10. The apparatus according to claim 9, wherein said means for rotatingsaid rack device about a vertical axis passing therethrough includes amotor positioned beneath said insulated chamber having a shaftprojecting vertically upwardly into said chamber, and wherein said lowerfr-ame section of said rack device includes a centrally disposedcylindrical element connected to the upper extremity of said motorshaft.

References Cited UNITED STATES PATENTS 870,680 11/1907 Karges 10811,927,396 9/1933 Freund et a1. 34--187 3,016,627 1/1962 Freund 34-1873,111,915 11/1963 Gray 211 X FREDERICK L. MATTESON, IR., PrimaryExaminer.

A. D. HERRMANN, Assistant Examiner.

1. APPARATUS FOR THE DEHYDRATION OF MATERIALS, COMPRISING: (A) ACHAMBER; (B) MEANS FOR PRODUCING A FLOW OF AIR THROUGH SAID CHAMBER; (C)A HEAT SOURCE DISPOSED WITHIN SAID CHAMBER; (D) MEANS FOR DIRECTING AFLOW OF HEATED AIR AWAY FROM SAID HEAT SOURCE; (E) A RACK DEVICESITUATED WITHIN SAID CHAMBER IN THE PATH OF SAID FLOW OF HEATED AIR,SAID RACK DEVICES INCLUDING (A) A LOWER FRAME SECTION, (B) A PLURALITYOF PARALLELLY DISPOSED STANDARDS CONNECTED TO SAID LOWER FRAME ANDPROJECTING UPWARDLY THEREFROM, (C) MEANS CONNECTED TO AT LEAST ONE OFSAID STANDARDS FOR PARTIALLY SUPPORTING A TRAY CHARGED WITH MATERIAL TOBE DEHYDRATED, (D) MEANS FOR FURTHER PARTIALLY SUPPORTING A TRAY CHARGEDWITH MATERIALS TO BE DEHYDRATED INTERCONNECTED WITH AT LEAST ONE OF THEOTHER OF SAID STANDARDS FOR LIMITED VERTICAL MOVEMENT WITH RESPECTTHERETO, SAID MEANS CONNECTED TO SAID ONE STANDARD FOR PARTIALLYSUPPORTING A TRAY AND SAID MEANS FOR FURTHER PARTIALLY SUPPORTING A TRAYINTERCONNECTED WITH SAID OTHER STANDARD FOR LIMITED VERTICAL MOVEMENTWITH RESPECT THERETO COOPERATING TO COMPLETELY SUPPORT A TRAY, (E) MEANSFOR MAINTAINING AT A PLURALITY OF PRESELECTED POINTS WITHIN THE RANGE OFLIMITED VERTICAL MOVEMENT THEREOF SAID MEANS FOR PARTIALLY SUPPORTING ATRAY INTERCONNECTED WITH SAID OTHER OF SAID STANDARDS, AS WELL AS (F)MEANS MOVABLY CONNECTED TO ONE OF SAID STANDARDS FOR RESTRAINING LATERALMOVEMENT OF A TRAY PLACED ON SAID RACK DEVICE; AND (F) MEANS FORROTATING SAID RACK DEVICE ABOUT A VERTICAL AXIS PASSING SUBSTANTIALLYCENTRALLY THERETHROUGH.